Seleucid Empire

The Seleucid Empire was a Greek/Hellenistic empire in the Middle East that was founded in 312 BC by Seleucus I of Syria. The Seleucid Empire were named for Seleucus, the king of the Seleucids until his assassination in 280 BC, and implemented Hellenistic culture upon the present-day countries of Iraq, Iran, Pakistan, the countries of Turkestan, Jordan, Syria, Lebanon, Palestine, and Israel. They declined after losing at the Battle of Magnesia in 190 BC to the Roman Republic and after the Maccabean Revolt of 167-160 BC, and Pompey the Great conquered the last Seleucid princes in 63 BC.

History
The Seleucid Empire was founded in 312 BC after the collapse of the Macedonian Empire of Alexander the Great, named for its creator Seleukos, a strategist for Alexander. It was made up of the ruins of the old Achaemenid Empire, consisting of Alexander's Middle Eastern territories (Egypt and Asia Minor apart). It was immediate neighbors with the Ptolemaic Empire, Antigonid Empire, Qidri, Satrapy of Media, Armavir, Cappadocia, Cyprus (their Cilician colony of Side), and Sardes.

With a capital at Seleucia, the empire continued their policy of implementing Greek culture on the Middle East, a dream that Alexander had during his lifetime. However, Alexander was dead and his empire gone, and Seleukos was one of the generals competing for the title of Macedonian king. His foes were Ptolemy I of Egypt and Antigonus I of Macedonia, two rival Diadochi who were his immediate neighbors. He also faced the Partians and Dahae to the east, and the Qidri, Palmyra, and Nabateans to the south.

Seleucus' first actions were to immediately fight the other Diadochi for power. He rivaled the Egyptians at first, but allied with them against Antigonus and defeated him at the Battle of Ipsus in 301 BC. However, the alliance broke down and he fought with Lysimachus of Thrace, a rival general who had swallowed up Thrace and Asia Minor whole. He conquered Lysimachus and his allies by 280 BC, when he was assassinated, having declared himself King of Macedon. In the end, Ptolemy contented himself with the Kingdom of Egypt and Demetrius took over as king of Macedon with the Antigonid Empire.

The Seleucids fell under the control of Antiochus I of Syria as of 270 BC, and Antiochus sought to expand his empire against his enemies. His first targets were the Parthian Empire, who were eastern Persian-Aryan tribes that raided his borders. He conquered Susa, one of their cities, and also defeated the Palmyrans in 269 BC. However, he met his end in 266 BC in the Battle of Jerusalem with Egyptian forces, having bribed Sidon to turn against Hekhemmut I of Egypt, causing war. His successor Alexander I of Syria conquered Jerusalem and forced the Egyptians out of Judaea, but warfare continued. Egypto-Greek rivalries continued in Judaea and Syria, but the Seleucids were also threatened to the north by the Kingdom of Pontus and the Greek Cities. Seleucus made peace with the Greek Cities while taking over some areas from the House of Pontus and the rebel settlements in Asia Minor.

Although the empire seemed great, it performed as all empires eventually do: it declined. The Egyptians may have lost many battles to the Seleucids, but contact with the Roman Republic prevented them from invading Egypt (on Roman insistance); a line in the sand was drawn by a Roman diplomat in front of Antiochus IV of Syria, and if he crossed it, he was told that war would follow, and he wisely stepped backwards. However, in the Fourth Syrian War of the 190s BC, they lost the Battle of Magnesia to the Romans. They declined, and in 167 BC, the Judaeans under Judah Maccabee rebelled against the mighty Greeks. In 160 BC, the rebellion ended as the Jews established the Hasamonean Empire in Israel, and the Seleucids declined.

The Seleucids were in control of only Syria by 100 BC, with Antioch as their capital. They remained in peace for the most part, as the Romans and Pontics fought up north in the Mithridatic Wars. The Seleucids were weakened by civil war, and Pompey took over the Seleucids in 63 BC. Rather than make the Seleucids vassals like the Jews and Egypt, Pompey transformed Syria into a Roman province.